Transcript: Interview with Lara Maister from Episode 042

In this episode of the You Are Not So Smart Podcast we sit down with cognitive neuroscientist Lara Maister who has married two fascinating and somewhat bizarre lines of research, one from psychology which reveals the unsettling truth behind hidden racial biases, and another from neuroscience that reveals how easily you transfer feelings of ownership from your familiar flesh onto inanimate objects and virtual-reality models.

David: Okay, so tell me Lara, how do we know that our body is our body?

Lara: Oh that’s quite a hard question. So I think intuitively, we just think well, “Surely I just know.” But actually it’s a sort of continuous, updating process. Where you take in lots of different information from all our different senses, and our body kind of – brain kind of integrates that to continually update how we know what’s part of our body, what’s not – and what we look like.

David: Your research into this is sort of absolutely amazing, because it involves a number of effects I don’t think most people are very familiar with. And at first, what you do kind of seems like some mad scientist experiment kind of thing. Changing ownership of your body with others and with objects. It’s really incredible stuff. And to understand it, I think there’s a couple of things we have to like make sense of. One thing you talk about a lot in this recent article is something called bodily resonance. What is bodily resonance?

Lara: Basically when we see another person experiencing a bodily state. So by that I mean quite a range of things. Like performing an action, feeling an emotion, feeling a touch on their bodies – or feeling pain for example. We don’t just see them experiencing that. We actually kind of resonate with them. So it’s been shown that we kind of – to some extent, experience the same bodily states that we’re seeing the other person experience. So, for example – if we saw someone performing an action, without realizing it – we might be quite likely to start mimicking that action. So if – perhaps we’re sitting in a room with someone who’s tapping their foot a lot, we’re a lot more likely to start tapping our foot in response to them. And we can see this – their level of the brain. So if we see someone performing an action, the areas of our brain that are activated when we – ourselves perform that action, are activated just the same when we see that action. And it’s the same with emotions and pain and touch experiences as well. So that’s what we kind of refer to as this sort of resonance between people. This sort of bodily resonance.

David: And this is – this has to do with – and people have heard this before, but this has to mirror neurons, correct?

Lara: Yeah, yeah. So I think kind of traditionally when we think about mirror neurons, we tend to think about parts of the brain in the pre-motor cortex are activated when we see someone performing an action. Just the same as when we perform that action ourselves. But more recently, these kind of mirror like behaviors in the brain have also been found in areas processing touch. So we show activity in parts of our somatosensory cortex when we see someone being touched on their bodies. Just the same as what would happen in our brains if we got touched. So there are quite a few areas of the brain now that seem to have these kind of mirror like properties.

David: And you mentioned something – this is a really interesting experiment. Where you see someone touching their face and you call it – this visual remapping of touch. What is happening in one of those kind of experiments?

Lara: So this is kind of a cool effect, and it’s quite a nice measure of this kinda bodily resonance. So what happens is – it’s been found that when someone gets touched on their face very, very gently – so they’re kind of – around the threshold of perception. People’s sensitivity to those touches on their face is increased when they see someone else being touched at that same moment. So what happens in practice is a participant has these little tactile stimulators attached to their face. And they get delivered very, very tiny little touches. And they have to say simply whether they feel a touch, whether they don’t feel a touch. And we’ve found that their accuracy is significantly improved when they’re sat with a person in front of them, getting touched at the same time. And that’s kind of behavioral evidence of this sort of somatosensory resonance. So it’s the idea that seeing someone else being touched kind of activates your own kind of touch areas, if you like? And it makes you more likely and more sensitive to perceived touch on your own face.

David: That’s so amazing, and so weird and so fascinating. Is there any speculation as to how this would have become part of our response to the world? As to how this is – is this adaptive, or is it just some sort of happy accident of evolution? What are your thoughts on that?

Lara: Well that’s interesting. I would think it would be pretty adaptive. So – for example – if you see someone in pain, and it’s someone you know in your close social group. I think it’d be pretty adaptive to sort of be able to detect that, and perhaps kind of respond appropriately to that. Because it – perhaps – more likely for you to have that painful event happen to yourself as well. So yeah, you can see why there might be sort of evolutionary benefits to a mechanism like that.

David: So this gets us to the really weird stuff. Which is – some research into this – specifically this visual remapping of touch, is that it seems to be as– Some of the scientists you’ve talked about – it seems to be modulated by the– How familiar the face is to you, or whether or not it’s in your – you consider something as part of your out group or your in group. Could you sort of explain how that is – how that changes how we feel when it comes to some of these bodily resonance things?

Lara: So I think that’s really interesting. And there’s a lot of different areas of research now that suggest that sort of – yeah this in group out group classification can really effect how we resonate with others. And it’s quite an automatic thing that we do when we meet someone new. We just automatically and unconsciously categorize them as either like me or not like me. And this sort of categorization can be based on so many different types of information. So one salient type of information would be racial group membership. But it could also be – how someone dresses, their political affiliations, what school they went to. All these different types of social information. But yeah – so taking the visual remapping of touch example. They found that if the person is looking at a face being touched, and that face belongs to a different racial group to their own race – they don’t show this effect so much. So they don’t show this resonance. And that’s kind of fascinating. And intuitively, I would think – okay well, maybe it’s because the face of the other race person is quite different perceptually to your own face. So maybe you just don’t remap. Because they look different. But actually, they’ve replicated this with political group membership as well. So obviously someone who belongs to a different political party to yourself doesn’t look different. But they just have different beliefs. So it shows that it’s not just perceptual characteristics that’s driving this. It’s not just that someone looks different. That that’s the reason why you’re not resonating. It’s actually how you categorize them as feeling different to yourself or similar.

David: That is surprising to me, and I’m sure to many people. Because it implies that our social and cultural attitudes and the cognition that surrounds all that is somehow being intertwined with actual physical feelings. And perceptions of – receiving input from sensory modalities and things like that. Is that – was that a surprising finding to you as well?

Lara: Yeah, I think everyone was really fascinated. There’s another study looking at empathy for pain. Which investigates this thing called the sort of – sensory motor brain response to pain. So when we see someone else in pain – for example experiencing a kind of painful event happening to them. Usually it’s a hand being stabbed with a needle or something nice like that. We find that this inhibits the corticospinal system, as if we ourselves were feeling that pain. So there’s various ways of measuring this. But one study by Alessio Avenanti, showed that when you see a hand of a racial out-group experiencing this painful stimulus – you don’t show that corticospinal inhibition. And I found that kind of – depressing finding. Because it’s such a sort of fundamental automatic level, it’s nothing to do with cognition as such. It’s nothing to do with like how you’re thinking about that person at that moment. It is just your kind of resonance. Your sort of physiological resonance with that person. And an interesting aspect of that study was – again – they showed that it wasn’t just because the hand looked different to your own. Because they had a control condition where they showed participants a bright purple hand. Just to check whether it was just visual similarity, or visual dissimilarity that was causing this – kind of this empathic response. And even more depressingly, they found that actually the empathic response to the purple hand feeling pain was completely normal. It was just the same as when you saw your racial in-group feeling pain. So it was just the racial out-group that was sort of culturally learned to be different. That showed the sort of suppressed empathic response.

David: That is insane. I mean it’s like a filter that overlays your experiences. Like it’s an additional response to the raw information that’s– It’s shocking. Like I can feel the doors opening to all these lines of research, to try to understand what’s going on there.

Lara: Yeah, I mean it’s some– It’s also interesting that they found, and actually a lot of these studies, they found that the reduction in your resonance with people from other races – quite strongly correlates with your kind of implicit racial biases. So these sort of changes in physiological bodily responses to people, is clearly quite directly linked to your sort of – way you think about these people. Your attitudes towards them.

David: It’s amazing. Yeah, because of the– The implied, and the implied attitude test – and there’s so much research into this. It’s all really, really interesting stuff. Where like they’ll have – they’ll show faces. They’ll show Caucasians. They’ll show them black faces. And then after that, you take a test where you look at like a hammer. And you have to determine whether or not it’s a tool or a weapon very quickly. And people tend to mistake – or tend to call things that are neutral weapons more often after seeing a black face, when they’re primed that way. There’s another one where there’s a fuzzy picture of a gun slowly comes into focus. And people who’ve been primed in a similar way will see it more quickly as a gun, than other people who are still trying to figure out what it is. And that’s why your research, the stuff that we’re getting to here is sort of – it messes with– It takes all the things that we’re talking about and sort of mushes them together. And you found some really crazy stuff. But to set the stage, I think we need to understand– The rubber hand illusion that you talked about. That’s crazy. Which is the – that’s putting the hand down and rubbing it and slowly feeling like your hand is the rubber hand.

Lara: Yeah.

David: If you go – you can go on YouTube, and watch someone do this. And they’ll – the knife will come down onto the fake hand, and when it hits it – people shriek. Because they have moved over. What is the enfacement illusion? That’s something I had never heard of before.

Lara: So that’s – it’s actually pretty much identical to the rubber hand illusion, just with faces. But instead of a rubber face, which would look pretty freaky – we use a real person’s face. So the idea’s the same. So we’ll have the participant sitting facing another person. So it can be video on a computer screen, which we’ve used quite often. But also it could be just a real person in front of them. And the crucial bit is where the experimenter touches the participant’s cheek at exactly the same time, and in synchronous rhythm with a touch on the other person’s cheek. And what this does is – the participant feels the touch on their own cheek, but sees the touch on the other person’s cheek. In exact synchrony. And it’s that synchrony that kind of elicits this feeling of ownership over the other person’s face. And it kind of develops this weird experience. Like you’re looking in a mirror, but seeing someone else’s face. And people report all sorts of crazy experiences during this. But we’ve also found really interesting things about what happens after the illusion. And one of them is that we actually change the way people remember what their own face looks like. And this is – bit of evidence showing how kind of malleable and how sort of plastic our idea of what we look like is. That we can change it so easily. But people actually think they look a little bit more like the other person than they did before the illusion. So that’s a really fascinating finding. ‘Cause you wouldn’t think that it would be so easy to change. But yeah, it is so.

David: It is, I mean I– I guess I’d always assumed that. I just have – these things are sort of set in my mind. But this research suggests that– Like you were saying, these mental representations of our own bodies, and our feelings of ownership. They’re malleable, they’re changeable. And it’s because they’re being constantly updated. Like you said before, is – that seems very strange, doesn’t it?

Lara: Yeah, it does in one way. But then, when you consider how much our appearances change over our lifetime as we grow and age – it kinda makes sense that the way we remember what we look like does have to be constantly updated. Otherwise we’d end up with a situation where one day we look in the mirror and don’t recognize ourselves. And it makes sense that every time we do look in the mirror, look down at our own bodies – that very, very subtle everyday changes are encoded somewhere in our brain, so that we’re not shocked by it the next time we look down at our bodies. So in that way, it does make sense that our brains can respond to these changes appropriately.

David: And it’s important to – it’s an odd thing to think about. But this – your feeling of ownership is a feeling. It’s like a – it’s almost – it is– The idea that you can – you look at your hand and you feel that you’re in control of it, and then it can be moved over into an artificial hand. Really shows there’s a – there’s something biological at play. There’s something – it’s not– This – our mental world is– The fact that it is plastic is astonishing to me. And you took this concept, and you sort of married it with trying to see if our social attitudes are also malleable. So if you could, could you sort of take me through this research that you did with the rubber hand, and playing around with social attitudes?

Lara: Yeah, so I think the idea came from – one interesting result of the rubber hand illusion. That actually, which is similar to the result I just talked about with the enfacement illusion. Where afterwards, participants think that they look a little bit more like the other person’s face. That also happens with the rubber hand illusion. So after experiencing the illusion, participants will think that the rubber hand is perceptually sort of – in terms of it’s visual appearance – more similar to their own hand. And this got us thinking that – could this work with hands that were very much different to your own perceptually? For example, a hand belonging to another racial group. So what we did was we gave Caucasian participants the rubber hand illusion with a black rubber hand. And we found that this difference in race of the rubber hand, had no effect on the strength of the illusion. So people feeling illusion, regardless of what the hand looks like in terms of it’s visual appearance. So we were kind of encouraged by the fact that people could experience ownership over – other race body. And therefore then, we ended up with this question – well, if we can kind of experience ownership over a body of another race, can we change how we feel towards that race? So that was the kind of – the basis of our research question.

David: So what happened? What was–? I understand that you do, this is sort of – you start with that, with some of these– This previous research. Sort of these things where you identify people have unconscious biases that we wish we didn’t have. We have no control over them, they’re automatic, they’re unconscious. And then you put them through this visual illusion thing. Just sort of take me through what happened with all that research.

Lara: Yeah so, what we did was – first we measured participant’s implicit racial biases. So obviously we can measure racial attitudes in 2 ways. We could do it explicitly by pretty much asking them with a questionnaire or something. But obviously that has problems with social desirability. So people aren’t honest on those type of questionnaires. So we use this implicit measure, called an implicit association test. That can assess people’s racial biases in a kind of unconscious way. So it’s kind of harder to fake basically. So we measure people’s baseline racial biases. And then we expose them to this rubber hand illusion with the hand of a racial out group. So in this case, it was Caucasian participants, so white participants seeing a black hand. And then after the illusion, we again measured their implicit racial attitudes one more time with the same tool. And what we found was that there was a significant decrease in their negative racial biases after experiencing the illusion with the black hand. And this decrease was correlated with the intensity of illusion that they felt. So there’s always a range of experiences that people have. So some people are very susceptible to these sort of bodily illusions, and have really, really strong feelings of ownership. Whereas some people aren’t so susceptible. And we’ve found that those people who were most susceptible to the illusion, felt really, really strong ownership over the black hand. Showed the biggest change in racial bias, so they became less biased.

David: And this was also done in, from – with other researchers. And this is crazy, but you can actually completely change ownership into a complete virtual body as well. Through like a virtual reality holodeck kind of experience. With modern day virtual reality technology, correct?

Lara: Yeah. So this was some research that was independently carried out by Mel Slater in his lab in Barcelona. And they used virtual reality to get people to embody virtual avatars. And they measure the effects on different aspects of social cognition. So in his study, they got white participants to embody a black avatar. And just move around this virtual environment. They could look down at their own bodies, and they’d see a black body. And there was also a mirror in the virtual environment – a virtual mirror, so they could go in front of the mirror, and they’d see what their own face looked like. So they gave participants a few minutes to kind of explore this environment and look at their own bodies. And then – again – they measured the racial bias. And independently they found pretty much the same results as what we’d found with the rubber hand. So they found a significant decrease in negative racial bias after embodying this black avatar.

David: That is amazing. And there was one other one too, which was the – as we were – we were talking about earlier. The experiment with feeling ownership of another face. What happened in that experiment – when racial bias was added to the – part of the experimental conditions?

Lara: Yeah so I think – that one used– Yeah, the enfacement illusion, with a black face as the enfaced face. And the – the sort of measure of interest with that one was the visual remapping and touch. Which we just spoke about. So they wanted to see whether experiencing ownership over a black face could increase your sort of sensory resonance with that person afterwards. And they did find that experiencing that enfacement illusion made you resonate more with these tactile experiences that you were seeing on the other person’s face. So it seemed to kind of alleviate the reduced resonance to racial out groups that we were talking about before.

David: Now to me – there’s a line in your– In your article, you say, “Changing your body, changes your mind.” And that’s part of the title too, “Changing your body – it changes your mind.” And different people have different opinions about whether or not you can change minds. Whether or not a person’s social attitudes are changeable. Their opinions about people who have come from other political tribes or people that are in different out groups. Whether it’s gender, race, age – any of that stuff. A lot of people feel like that’s like – it’s locked in stone, and there has to be like a generational – a turn for change to take place. But your research suggests that social attitudes are malleable. What is your – what are your thoughts on that aspect of this research?

Lara: Well we’ve definitely shown that – at least on the short term, social attitudes are really malleable. And we’re looking at implicit attitudes here. So they’re not sort of under cognitive control. And we’re seeing changes – significant changes after only 2 minutes of experiencing these illusions. But it’s important to point out that we’ve not actually yet tested how long these changes last. So actually we’re in the process now of investigating whether these changes in racial bias extend beyond 1 week, 2 weeks.

David: Oh yeah, yeah.

Lara: But actually – currently we don’t have that data yet. So all we know is that we can elicit an immediate change. Because there’s so many different influences on these social attitudes, of course if we elicited an illusion – we changed a social attitude. And then someone went right back into their normal society where these sort of negative stereotypes were enforced again – I think it would probably undo it pretty quickly.

David: Right.

Lara: So yeah, it’s kind of a question of – the fact that there’s so many different influences of these social attitudes. That just changing one temporarily is probably not going to alter any of the others.

David: So what do you think is the process that’s in play here? Like what is – like when you try to – after you’ve done this research and you’re looking at it, what do you think– What is the, what is occurring in the processing of this information and self-association and all that sort of stuff?

Lara: That’s a really hard question. And we’re still not sure. Because what we’re doing with the bodily illusions is changing something very low level, and very perceptual. But we’re actually seeing an influence on something that’s quite kind of conceptual. If you like, an implicit social attitude. So it’s a case of working out exactly what mechanism links these 2 things together. And we think it might be something to do with a change in perceived similarity between yourself and the person that you’re embodying. The person you’re feeling the illusion over. So if you – after the illusion, perceive that person as looking more similar to yourself, we suspect that this kind of has a knock on effect to perceived similarity in other domains. So if you think that someone looks like you, there’s evidence to suggest that that makes you also think that the other person thinks like you or is like you. So we think that it kind of has – this kind of perceived similarity has a sort of knock on effect in other aspects of perceived similarity. And so, for example – if I saw someone who looked like me, there’s evidence to suggest that – I just assume that that person has similar beliefs to me too. So we kind of generalize this perception of similarity. And so that might be what is at play here. But we’re not quite sure yet, and we have to think of ways to kind of work out what mechanisms are at play.

David: That’s so cool. That’s such great research. I know people are going to want to keep up with you. Like what – like they’ll want to find you and learn more about what you’re up to. How can someone do that?

Lara: So we’ve got a lab website, our lab in London is run by Professor Manos Tsakiris. And we’re at Royal Holloway University of London. So if you Google my name, and that university, you should be able to find me. And we’ve got all our papers on there, and our kind of current research projects. So in addition to this stuff on race, we’re also looking at how these bodily illusions can influence things like emotion recognition and empathy. And all sorts of other things like that. So yeah, that’s kind of a good repository for all of that.

David: Great. Well look, thank you so much for chatting with me. And I love what you’re doing. I think it’s really important work. And I really – I just – I hope you have great success in the future in figuring out how all this really, really plays out and how it works together. And how it connects to other research. So best wishes in all of that.